为解决蔬菜中农药多残留检测存在的基质复杂、干扰大和浓度低等技术困难，本研究建立了一种新的蔬菜中56种农药多残留的液相色谱-串联质谱的分析方法。蔬菜样品经改良QuEChERS方法前处理，即用含1%（V/V）乙酸的乙腈溶液提取，并加入氯化钠和无水乙酸钠盐析，以N-丙基乙二胺净化，直接进样分析。以乙腈和水溶液(含5 mM的乙酸铵和0.1%（V/V）甲酸)为流动相，经C18色谱柱（4.6×100 mm、2.6 μm）分离，电喷雾正离子（ESI+）模式电离，多反应监测（MRM）模式检测。结果表明，56种农药在2 μg/L~100 μg/L有良好线性，其相关系数大于0.99，检出限均低于0.01 mg/kg，在3个添加水平下的回收率为65.8%~114.0%，相对标准偏差为0.1%~14.5%。该方法简单、快速、可靠，可用于蔬菜质量安全风险评估中多种类农药残留的快速筛查分析。

A new method for analysis of 56 pesticide residues in vegetables using modified QuEChERS-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established to solve the technical difficulties of complex components, interference and low concentration. Vegetable samples were pretreated bymodified QuEChERS, which was extracted with acetonitrile containing 1% (V/V) acetic acid, and then salted out with sodium chloride and anhydrous sodium. purified with primary secondary amine, samples was analyzed by HPLC-MS/MS. The extract was separated on a C18 column (4.6×100 mm, 2.6 μm) using acetonitrile and aqueous solution as the mobile phase (containing 5 mM ammonium acetate and 1% (V/V) acetic acid), ionized in electrospray ion (ESI+) mode and then analyzed in multiple-reaction monitoring (MRM) mode. The results showed that the 56 pesticide residues showed good linear correlation in the range of 2.0 μg/L to 100 μg/L with the correlation coefficients over 0.99. The limits of detection were less than 0.01 mg/kg, and the recoveries were ranged of 65.8%~114.0% at three spiked levels in vegetables with the relative standard deviations of0.1%~14.5%. This proposed method is rapid, simple, low-cost and effective, which can be applied to rapid screening and analysis of pesticide residues in vegetables for the risk assessments of quality and safety.

2013年广东省科技计划项目（2013B020311005）；2015年广东省优秀青年教师培养项目（YQ2015188）